U.S. patent number 8,671,906 [Application Number 13/042,952] was granted by the patent office on 2014-03-18 for clutch actuator mounting structure for internal combustion engine.
This patent grant is currently assigned to Honda Motor Co., Ltd.. The grantee listed for this patent is Yasushi Fujimoto, Kinya Mizuno, Yoshiaki Tsukada. Invention is credited to Yasushi Fujimoto, Kinya Mizuno, Yoshiaki Tsukada.
United States Patent |
8,671,906 |
Fujimoto , et al. |
March 18, 2014 |
Clutch actuator mounting structure for internal combustion
engine
Abstract
A clutch actuator mounting structure for internal combustion
engine has excellent maintainability such that clutch actuator
maintenance and the like can be carried out without dismounting an
engine case. The clutch actuator mounting structure for an internal
combustion engine includes, in the engine case, a power
transmission mechanism designed to transmit rotational power of a
crankshaft to an output shaft through a shift clutch and a
transmission. The engine case is formed with a clutch actuator
containing part in which a clutch actuator for engaging/disengaging
the shift clutch is contained. The clutch actuator containing part
has a clutch actuator mounting/dismounting port through which to
mount and dismount the clutch actuator. The clutch actuator
mounting/dismounting port is formed to be exposed to the
exterior.
Inventors: |
Fujimoto; Yasushi (Wako,
JP), Mizuno; Kinya (Wako, JP), Tsukada;
Yoshiaki (Wako, JP) |
Applicant: |
Name |
City |
State |
Country |
Type |
Fujimoto; Yasushi
Mizuno; Kinya
Tsukada; Yoshiaki |
Wako
Wako
Wako |
N/A
N/A
N/A |
JP
JP
JP |
|
|
Assignee: |
Honda Motor Co., Ltd. (Tokyo,
JP)
|
Family
ID: |
43875250 |
Appl.
No.: |
13/042,952 |
Filed: |
March 8, 2011 |
Prior Publication Data
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Document
Identifier |
Publication Date |
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US 20110220057 A1 |
Sep 15, 2011 |
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Foreign Application Priority Data
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Mar 11, 2010 [JP] |
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2010-053925 |
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Current U.S.
Class: |
123/197.5;
192/112 |
Current CPC
Class: |
F16D
13/58 (20130101); F16D 2300/12 (20130101) |
Current International
Class: |
F02B
75/32 (20060101) |
Field of
Search: |
;123/195C,196R,196CP,198E,197.5 ;180/292,312,313
;192/112,48.061,48.064,84.6 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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202006019190 |
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Apr 2008 |
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DE |
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0389957 |
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Oct 1990 |
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EP |
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1696147 |
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Aug 2006 |
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EP |
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1998063 |
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Dec 2008 |
|
EP |
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2008-138541 |
|
Jun 2008 |
|
JP |
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2008/071185 |
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Jun 2008 |
|
WO |
|
Primary Examiner: Nguyen; Hung Q
Attorney, Agent or Firm: Westerman, Hattori, Daniels &
Adrian, LLP
Claims
We claim:
1. A clutch actuator mounting structure for an internal combustion
engine, comprising: an engine case including a clutch actuator
containing part adapted to house a clutch actuator for
engaging/disengaging a shift clutch, said clutch actuator
containing part having a clutch actuator mounting/dismounting port
which is exposed to an exterior of said engine case, wherein the
clutch actuator is configured to be mounted and dismounted through
said clutch actuator mounting/dismounting port. wherein said engine
case is mountable on a lateral side of a crankcase which rotatably
supports a crankshaft thereon; wherein said clutch actuator
containing part projects to a lateral side of said engine case,
wherein the internal combustion engine is mountable on a vehicle
with the crankshaft oriented in a left-right direction; wherein the
shift clutch is provided at an end of a transmission main shaft
which projects into an inside of the engine case, said transmission
main shaft being provided inside the crankcase; wherein said engine
case further comprises a bulge containing part in which the shift
clutch and a gear pair for transmitting power from the crankshaft
to the shift clutch are mounted, the bulge containing part being
bulged to the lateral side of said engine case; and wherein said
clutch actuator containing part projects into a space on a lower
side of said bulge containing part.
2. The clutch actuator mounting structure according to claim 1,
wherein said engine case is configured to be provided with an oil
filter so as to overlap, in front view, with a front side of said
clutch actuator containing part, in the space on the lower side of
said bulge containing part.
3. The clutch actuator mounting structure according to claim 2,
wherein said engine case further comprises an oil filter
housing.
4. The clutch actuator mounting structure according to claim 3,
wherein said clutch actuator containing part is formed inward of
said oil filter housing, in a vehicle body width direction.
5. The clutch actuator mounting structure according to claim 4,
wherein a longitudinal direction of said clutch actuator containing
part is oriented in a vehicle front-rear direction; and wherein
said oil filter housing is formed such that a cylindrical filter
element of the oil filter contained in said oil filter housing has
a center axis oriented in the vehicle front-rear direction.
6. The clutch actuator mounting structure according to claim 5,
wherein said clutch actuator mounting/dismounting port of said
clutch actuator containing part faces rearward in the vehicle
front-rear direction; and wherein a filter element
mounting/dismounting port of said oil filter housing faces forward
in the vehicle front-rear direction.
7. The clutch actuator mounting structure according to claim 6,
wherein a lower end of said clutch actuator containing part is
proximate to or overlapping with a lower end edge of said engine
case; and wherein an upper end of said oil filter housing is
located substantially at the same vertical position as an upper end
of said clutch actuator containing part.
8. The clutch actuator mounting structure according to claim 7,
wherein the shift clutch is a twin clutch and a pair of clutch
actuators; wherein the pair of clutch actuators for respectively
driving clutches of the twin clutch by oil pressure are disposed on
a front lower side of the twin clutch; wherein a pair of control
oil passages are formed at an outside surface of said engine case,
the pair of control oil passages being oblique to the center axis
of the cylindrical filter element of the oil filter contained in
said oil filter housing, said pair of control oil passages
extending rectilinearly in parallel to each other; and wherein said
pair of control oil passages supply a working oil from the clutch
actuators to the corresponding shift clutches.
9. The clutch actuator mounting structure according to claim 8,
further comprising: a first control oil pressure sensor projecting
upwardly at a substantially central position of an upper-side one
of said pair of control oil passages; and a second control oil
pressure sensor projecting rearwardly in lower-side one of said
pair of control oil passages, at a height position between the
shift clutch and the pair of clutch actuators.
10. The clutch actuator mounting structure according to claim 9,
further comprising: a discharge oil pressure sensor for detecting
the oil pressure of oil discharged from an oil pump and led into
the oil filter, said discharge oil pressure sensor projecting
forwardly on the oil filter.
11. The clutch actuator mounting structure according to claim 10,
wherein the discharge oil pressure sensor is mounted to a filter
cover member which closes the filter element mounting/dismounting
port, said filter cover member being disposed forward of the oil
filter housing of the oil filter, in the vehicle front-rear
direction.
Description
TECHNICAL FIELD
A structure for mounting a clutch actuator for engaging and
disengaging a shift clutch of an internal combustion engine is
disclosed.
BACKGROUND OF THE INVENTION
An internal combustion engine with such a clutch actuator mounted
to an engine case is disclosed in Japanese Patent Laid-open No.
2008-138541.
In the internal combustion engine disclosed in Japanese Patent
Laid-open No. 2008-138541, which is equipped with a twin clutch
type transmission, a twin clutch operated by oil pressure is
provided at an end portion of a main shaft of the transmission, and
a clutch cover mounted to a right side surface of a crankcase is
projected to the right side to cover the twin clutch.
In addition, along a mating surface of the crankcase for mating
with the clutch cover, the crankcase is provided at its inner
surface with a clutch actuator containing part bulged to the inner
side. Further, a clutch actuator for engaging and disengaging the
twin clutch is inserted into the clutch actuator containing part
through an opening formed in that surface of the clutch actuator
containing part which is the same as the mating surface, and the
clutch actuator is detachably mounted.
In the manner of extending from the clutch actuator containing part
of the crankcase, a control oil passage for supplying a working oil
to the shift clutch is formed in communication with the inside of a
side wall of the crankcase and the inside of a side wall of the
clutch cover.
SUMMARY OF THE INVENTION
As above-mentioned, the structure for mounting the clutch actuator
disclosed in Japanese Patent Laid-open No. 2008-138541 is disposed
on the inner side of the crankcase and the clutch cover. Therefore,
for performing clutch actuator maintenance or the like, the clutch
cover which is formed with the control oil passage and large in
size must be dismounted, and workability is poor accordingly.
A clutch actuator mounting structure for internal combustion engine
is provided which has excellent maintainability such that clutch
actuator maintenance and the like can be carried out without
dismounting an engine case.
In a first aspect, there is provided a clutch actuator mounting
structure for an internal combustion engine including, in an engine
case, a power transmission mechanism designed to transmit
rotational power of a crankshaft to an output shaft through a shift
clutch and a transmission, characterized in that the engine case is
formed with a clutch actuator containing part in which a clutch
actuator for engaging/disengaging the shift clutch is contained;
and the clutch actuator containing part has a clutch actuator
mounting/dismounting port through which to mount and dismount the
clutch actuator, the clutch actuator mounting/dismounting port
being formed to be exposed to the exterior.
In a second aspect, the engine case formed with the clutch actuator
containing part is a case cover for covering the shift clutch on a
lateral side of a crankcase for rotatably supporting the crankshaft
thereon, and the clutch actuator containing part is formed to
project to a lateral side of the case cover.
In a third aspect, the internal combustion engine is mounted on a
vehicle with the crankshaft oriented in a left-right direction; the
shift clutch is provided at that shaft end of a main shaft in the
transmission provided inside the crankcase which is projected into
the inside of the case cover; the case cover has a bulge containing
part in which a gear pair for transmitting power from the
crankshaft to the shift clutch and the shift clutch are contained,
the bulge containing part being bulged to a lateral side; and the
case cover has the clutch actuator containing part projected into a
space on the lower side of the bulge containing part.
In a fourth aspect, the case cover is provided with an oil filter
so as to overlap, in front view, with the front side of the clutch
actuator containing part in the space on the lower side of the
bulge containing part of the case cover.
In a fifth aspect, the oil filter has an oil filter housing in
which to contain a filter element, the oil filter housing being
projectingly formed as part of the case cover.
In a sixth aspect, the clutch actuator containing part is formed on
the inner side relative to an outside part of the oil filter
housing in a vehicle body width direction.
In a seventh aspect, the clutch actuator containing part is formed
to have its longitudinal direction oriented in a front-rear
direction, and the oil filter housing is formed in such a shape
that a filter element being cylindrical in shape is contained in
the oil filter housing with the center axis of the cylinder
oriented in the front-rear direction.
In an eighth aspect, the clutch actuator containing part is formed
with the clutch actuator mounting/dismounting port oriented
rearward; and the oil filter housing is formed with a filter
element mounting/dismounting port through which to mount and
dismount the filter element, the filter element
mounting/dismounting port being oriented forward.
In a ninth aspect, the clutch actuator containing part is formed at
a vertical position such that its lower end is proximate to or in
contact with a lower end edge of the case cover, and the oil filter
housing has its upper end located at substantially the same
vertical position as an upper end of the clutch actuator containing
part.
In a tenth aspect, the shift clutch is a twin clutch; the two
clutch actuators for respectively driving clutches of the twin
clutch by oil pressure are provided on a front lower side of the
twin clutch; and a pair of control oil passages for supplying a
working oil from the clutch actuators to the corresponding shift
clutches respectively are formed at an outside surface of the case
cover in the state of being oriented obliquely and extending
rectilinearly in parallel to each other.
In an eleventh aspect, a first control oil pressure sensor is
upwardly projectingly provided at a substantially central position
of a first control oil passage which is an upper-side one of the
pair of control oil passages oriented obliquely; and a second
control oil pressure sensor is rearwardly projectingly provided in
a second control oil passage which is a lower-side one of the pair
of control oil passages, at a height position between the shift
clutch and the clutch actuators.
In a twelfth aspect, a discharged oil from an oil pump is led into
the oil filter; and a discharge oil pressure sensor for detecting
the oil pressure of the discharged oil is forwardly projectingly
provided on the oil filter.
In a thirteenth aspect, the discharge oil pressure sensor is
mounted to a filter cover member for closing the filter element
mounting/dismounting port, which is oriented forward, of the oil
filter housing of the oil filter.
According to the clutch actuator mounting structure for the
internal combustion engine of the first aspect, the clutch actuator
containing part formed as part of the engine case has the clutch
actuator mounting/dismounting port formed to be exposed to the
exterior. This ensures that the clutch actuator contained in the
clutch actuator containing part can be put in and out through the
clutch actuator mounting/dismounting port without dismounting the
engine case, and maintainability is extremely good accordingly.
According to the clutch actuator mounting structure for the
internal combustion engine of the second aspect, the case cover for
covering the shift clutch has the clutch actuator containing part
formed to project to a lateral side, and the clutch actuator
mounting/dismounting port formed as part of the clutch actuator
containing part is exposed to the exterior. Therefore, the clutch
actuator can be put in and out through the clutch actuator
mounting/dismounting port of the case cover without dismounting the
case cover, and maintainability is extremely good accordingly.
In this structure, the clutch actuator containing part formed to
project to a lateral side of the case cover is formed with the
clutch actuator mounting/dismounting port exposed to the exterior,
so that the clutch actuator mounting structure can be
simplified.
According to the clutch actuator mounting structure for the
internal combustion engine of the third aspect, the clutch actuator
containing part is projectingly formed by utilizing the space on
the lower side of that bulge containing part of the case cover in
which the gear pair for transmitting power from the crankshaft to
the shift clutch at an end portion of the main shaft and the shift
clutch are contained and which is formed to be bulged to a lateral
side. This ensures that the clutch actuator containing part can be
formed without enlarging the internal combustion engine in overall
left-right width or overall front-rear width, and it is therefore
possible to obviate an enlargement of the size of the internal
combustion engine.
According to the clutch actuator mounting structure for the
internal combustion engine of the fourth aspect, the case cover is
provided with the oil filter so as to overlap, in front view, with
the front side of the clutch actuator containing part in the space
on the lower side of the bulge containing part of the case cover.
This ensures that the clutch actuator containing part is provided
on the rear side while the oil filter is provided on the front
side, in the space on the lower side of the bulge containing part
of the case cover. Therefore, the oil filter can be provided
without enlarging the internal combustion engine in overall
left-right width or overall front-rear width. Consequently, it is
possible to obviate an enlargement of the size of the internal
combustion engine.
According to the clutch actuator mounting structure for the
internal combustion engine of the fifth aspect, the oil filter has
the oil filter housing in which to contain the filter element, the
oil filter housing being projectingly formed as part of the case
cover. Thus, the oil filter housing is not formed separately from
the case cover but formed integrally with the case cover, which
leads to a reduction in the number of component parts and to
enhanced maintainability.
According to the clutch actuator mounting structure for the
internal combustion engine of the sixth aspect, the clutch actuator
containing part is formed on the inner side relative to the outside
part of the oil filter housing in the vehicle body width direction.
Therefore, the oil filter housing serves as a shield by which the
clutch actuator can be protected from flying stones and the
like.
According to the clutch actuator mounting structure for the
internal combustion engine of the seventh aspect, the clutch
actuator containing part is formed to have its longitudinal
direction oriented in the front-rear direction, and the oil filter
housing is formed in such a shape that the filter element being
cylindrical in shape is contained in the oil filter housing with
the center axis of the cylinder oriented in the front-rear
direction. This ensures that both the oil filter housing and the
clutch actuator containing part formed in the space on the lower
side of the bulge containing part of the case cover can be made
small in vertical width and left-right width, so that the internal
combustion engine as a whole is not enlarged in vertical width or
left-right width. In addition, with the clutch actuator containing
part and the oil filter housing set proximate to each other, it is
possible to obviate an enlargement of the size of the internal
combustion engine.
According to the clutch actuator mounting structure for the
internal combustion engine of the eighth aspect, the clutch
actuator containing part is formed with the clutch actuator
mounting/dismounting port oriented rearward, and the oil filter
housing is formed with a filter element mounting/dismounting port
through which to mount and dismount the filter element, the filter
element mounting/dismounting port being oriented forward. This
makes it possible to mount and dismount the clutch actuators and
the filter element without interference between the clutch actuator
containing part and the oil filter housing which are laid out
proximate to each other. Consequently, easy maintenance can be
achieved.
According to the clutch actuator mounting structure for the
internal combustion engine of the ninth aspect, the clutch actuator
containing part is formed at a vertical position such that its
lower end is proximate to or in contact with the lower end edge of
the case cover. This ensures that a lowering of the center of
gravity can be contrived by lowering the clutch actuator containing
part as much as possible. In addition, the oil filter housing has
its upper end located at substantially the same vertical position
as the upper end of the clutch actuator containing part. This
enables effective utilization of the space on the upper side of the
clutch actuator containing part and the oil filter housing which
have their upper ends at substantially the same vertical
position.
According to the clutch actuator mounting structure for the
internal combustion engine of the tenth aspect, the two clutch
actuators for respectively driving clutches of the twin clutch by
oil pressure are provided on the front lower side of the twin
clutch, and the pair of control oil passages for supplying the
working oil from the clutch actuators to the corresponding shift
clutches respectively are formed at the outside surface of the
right case cover in the state of being oriented obliquely and
extending rectilinearly in parallel to each other. Therefore, on
the rear side of the clutch actuators and on the lower side of the
twin clutch, where the pair of control oil passages do not
interfere, a space which is opened on the rear side and the lower
side and the outer side and which is suitable for putting the
driver's foot can be secured near the case cover.
According to the clutch actuator mounting structure for the
internal combustion engine of the eleventh aspect, the first
control oil pressure sensor is upwardly projectingly provided at
the substantially central position of the first control oil passage
which is the upper-side one of the pair of control oil passages
oriented obliquely, and the second control oil pressure sensor is
rearwardly projectingly provided at the second control oil passage
which is the lower-side one of the pair of control oil passages, at
a height position between the shift clutch and the clutch
actuators. This ensures that the first control oil pressure sensor
and the second control oil pressure sensor which enhance
performance of control of the shift clutch can be provided in a
compact fashion while avoiding interference with other component
parts.
According to the clutch actuator mounting structure for the
internal combustion engine of the twelfth aspect, the oil
discharged from the oil pump is led into the oil filter, and the
discharge oil pressure sensor for detecting the oil pressure of the
discharged oil is forwardly projectingly provided on the oil
filter. This ensures that the discharge oil pressure sensor can be
provided while utilizing the space on the front side of the oil
filter and while obviating, as securely as possible, the projection
of the discharge oil pressure sensor from the internal combustion
engine.
According to the clutch actuator mounting structure for the
internal combustion engine of the thirteenth aspect, the discharge
oil pressure sensor is mounted to the filter cover member for
closing the filter element mounting/dismounting port, which is
oriented forward, of the oil filter housing of the oil filter.
Therefore, by preliminarily mounting the discharge oil pressure
sensor to the filter cover member (87) and handling them as one
body, it is possible to enhance workability.
BRIEF DESCRIPTION OF THE DRAWINGS
The advantages of the invention will become apparent in the
following description taken in conjunction with the drawings,
wherein:
FIG. 1 is a right side view of a motorcycle on which an internal
combustion engine is mounted;
FIG. 2 is a right side view of the internal combustion engine;
FIG. 3 is a sectional view taken along line III-III of FIG. 2;
FIG. 4 is a sectional view taken along line IV-IV of FIG. 2;
FIG. 5 is an exploded right side view of a major part of the
internal combustion engine;
FIG. 6 is an exploded sectional view of the major part;
FIG. 7 is a right side view (outside view) of the right case
cover;
FIG. 8 is a left side view (inside view) of the right case
cover;
FIG. 9 is a rear view (view taken along arrow IX of FIG. 7) of the
right case cover;
FIG. 10 is a front view (view taken along arrow X of FIG. 7) of the
right case cover;
FIG. 11 is a sectional view (sectional view taken along line XI-XI
of FIG. 7) of the right case cover;
FIG. 12 is an outside view of a clutch actuator cover member;
FIG. 13 is an inside view of the clutch actuator cover member;
FIG. 14 is an outside view of a filter cover member;
FIG. 15 is an inside view of the filter cover member;
FIG. 16 is a right side view of a control oil pump; and
FIG. 17 is a right side view, with a major part in section, showing
the condition where the right case cover is put on the control oil
pump.
DETAILED DESCRIPTION OF THE INVENTION
Now, an embodiment will be described below, based on FIGS. 1 to
17.
FIG. 1 is a right side view of a motorcycle 130 on which an
internal combustion engine according to this embodiment is
mounted.
In FIG. 1, a body frame 2 of the motorcycle 1 includes a head pipe
3, main frames 4 extending obliquely rearward from the head pipe 3,
a center frame 5 extending downward from the rear ends of the main
frames 4, a down frame 6 extending downward from the head pipe 3,
seat stays 7 extending rearward from an upper portion of the center
frame 5, and a mid frame 8 bridgingly interposed between a rear
portion of the center frame 5 and rear portions of the seat stays
7.
A front fork 10 supporting a front wheel 9 thereon is steerably
supported on the head pipe 3, and a steering handle 11 is connected
to an upper portion of the front fork 10.
In addition, a rear fork 13 supporting a rear wheel 12 thereon is
vertically swingably supported through a pivot bolt 25 of the
center frame 5.
An internal combustion engine E is, for example, a 2-cylinder,
4-stroke internal combustion engine, and is supported by the main
frame 4, the center frame 5 and the down frame 6.
Rotational power of an output shaft of the internal combustion
engine E is transmitted to the rear wheel 12 through a rear wheel
driving chain 15.
A fuel tank 16 is mounted between the left and right main frames 4,
and a tandem type seat 17 on which a driver P and a pillion
passenger can be seated is mounted on the left and right seat stays
7 on the rear side of the fuel tank 16.
As shown in FIG. 1, on a right side surface of a vehicle body, a
step holder 20 is provided at a joint between a lower portion of
the center frame 5 and the mid frame 8, and a foot step 21 is
projectingly provided on the step holder 20.
On a left side surface of the vehicle body, also, a foot step 21 is
provided at a position in left-right symmetry with the position of
the above-mentioned foot step 2.
The internal combustion engine E is mounted in a horizontal posture
on the body frame 2, with its crankshaft 30 oriented in the
left-right direction, which is the vehicle body width direction.
The crankshaft 30 is rotatably supported between an upper crankcase
31U and a lower crankcase 31L into which a crankcase is bisected,
with bearings therebetween.
Referring to FIG. 2, a cylinder block 32, a cylinder head 33 and a
cylinder head cover 34 which are sequentially stacked and slanted
to the front side are provided in such a manner as to project along
a forwardly upward direction from the upper crankcase 31U.
The lower side of the lower crankcase 31L is closed with an oil pan
39.
A main shaft 35 of a transmission T is rotatably borne on the upper
crankcase 31U at a slightly obliquely upper position on the rear
side of the crankshaft 30 and in parallel to the crankshaft 30,
through bearings 36, 36 therebetween. At an obliquely lower
position on the rear side of the main shaft 35, a counter shaft 37
as an output shaft is rotatably borne between the upper crankcase
31U and the lower crankcase 31L, through bearings 38, 38
therebetween (see FIGS. 2 and 3).
Referring to FIG. 3, the main shaft 35 of the transmission T has a
structure wherein a main outer shaft 35o is fitted over a main
inner shaft 35i so as to be capable of relative rotation, and the
main shafts are provided respectively with pluralities of drive
gears m. A plurality of driven gears c provided on the counter
shaft 37 and the corresponding drive gears m are normally meshed
with each other.
The main outer shaft 35o and the main inner shaft 35i rightwardly
penetrating the bearing 36 fitted to a right side wall of the upper
crankcase 31U are provided thereon with a twin clutch 41 composed
of a pair of a first friction clutch 41A and a second friction
clutch 41B. A primary driven gear 43 is fitted to clutch outers of
both the clutches.
Engagement/disengagement of the first friction clutch 41A and the
second friction clutch 41B is controlled respectively by oil
pressures supplied through in-shaft oil passages 49a and 49b formed
on the outer side and the inner side in the inside of the main
shaft 35, whereby shifting of the transmission T is conducted.
A right case cover 70 is put on a right side surface of a crankcase
obtained by uniting the upper crankcase 31U and the lower crankcase
31L.
The friction clutches 41A and 41B provided on the right side
relative to the right side walls of the upper and lower crankcases
31U and 31L, the primary driven gear 43, a primary drive gear 44
fitted to the crankshaft 30 and meshed with the primary driven gear
43, etc. are covered by the right case cover 70.
In addition, a control oil pump 50 provided at a front portion of
the right side wall of the lower crankcase 31L is also covered by
the right case cover 70 (see FIG. 2).
Referring to FIG. 4, a control oil pump case 51 is formed with a
circular recess 51d opened on the left side for containing therein
an inner rotor 53 and an outer rotor 54 which are provided
respectively on the inner and outer sides and are meshed with each
other. The circular recess 51d is covered with a partition plate 57
brought into contact with the oil pump case 51 from the left
side.
A lubricating oil pump 60 is provided on the left side of the
partition plate 57, with a pump drive shaft 52 disposed in common
for the lubricating oil pump 60 and the control oil pump 50.
The lubricating oil pump 60 is formed with a circular recess 61d
opened on the right side for containing therein an inner rotor 63
and an outer rotor 64 which are provided respectively on the inner
and outer sides and are meshed with each other. The circular recess
61d is covered with the partition plate 57 brought into contact
with the lubricating oil pump case 61 from the right side.
In other words, the partition plate 57 is interposed between the
control oil pump case 51 and the lubricating oil pump case 61,
thereby partitioning the control oil pump 50 and the lubricating
oil pump 60 from each other.
The pump drive shaft 52 provided in common for both the oil pumps
50 and 60 is rotatably borne, with both its ends borne on the
control oil pump case 51 and the lubricating oil pump case 61 and
with its center borne on the partition plate 57, while being
oriented in the left-right direction.
Referring to FIG. 4 and to FIG. 16, which is a right side view of
the control oil pump case 51, the circular recess 51d is formed in
a mating surface of the control oil pump case 51 for mating with
the partition plate 57, whereas a suction oil passage 55 dug to be
deeper than the circular recess 51d is formed along a little less
than half a circumference around the front side of a bearing
circular hole 51b of the pump drive shaft 52 and is formed to
further extend downward and expand largely to the front and rear
sides.
On the other hand, a discharge oil passage 56 dug to be deeper than
the circular recess 51d is formed along a little less than half a
circumference around the rear side of the bearing circular hole 51b
and is formed to further extent in a rearwardly downward direction
toward the filter case 61.
The partition plate 57 brought into contact with the mating surface
of the control oil pump case 51 has a circular suction port 57h
bored correspondingly to that portion of the suction oil passage 55
which is expanded rearward. Though not shown, a suction pipe
extending from an oil strainer disposed along a bottom surface of
the oil pan 39 is connected to the suction port 57h.
The control oil pump case 51 is formed with a discharge port 51h
opened in its portion on the rear side of the discharge oil passage
56 (see FIG. 16).
Therefore, when the control oil pump 50 is driven, an oil
collecting in the oil pan 39 is sucked into the suction oil passage
55 through the oil strainer, and the discharged oil is passed
through the discharge oil passage 56 to be led through the
discharge port 51h to an oil filter which is provided at the right
case cover 70, as will be described later.
Incidentally, in that portion of the suction oil passage 55 which
is expanded rearward, a relief valve device 58 as an oil return
mechanism is fitted in the state of being oriented in a direction
orthogonal to the pump drive shaft 52. A valve element 59 of the
relief valve device 58 fronts on the discharge oil passage 56. When
the discharge oil pressure exceeds a predetermined pressure, a
movement of the valve element 59 results in opening of the valve,
whereby the discharge oil passage 56 and the suction oil passage 55
are made to communicate with each other, and a portion of the oil
discharged into the discharge oil passage 56 is returned into the
suction oil passage 55. Consequently, an adjustment is made so that
the discharge oil pressure would not reach or exceeds a
predetermined oil pressure.
The above-mentioned control oil pump 50 provided at a front portion
of the right side wall of the lower crankcase 31L is covered with
the right case cover 70 from the right side.
Now, the structure of the right case cover 70 will be described
below, based mainly on FIGS. 7 to 11.
A right side view of the right case cover 70 is shown in FIG. 7, a
left side view of the same in FIG. 8, a rear view of the same in
FIG. 9, a front view of the same in FIG. 10, and a sectional view
(sectional view taken along line XI-XI of FIG. 7) of the same is
shown in FIG. 11.
The right case cover 70 has a structure in which a roughly upper
half portion of its side wall facing the right crankcase 31R is
bulged rightward to form a bulge containing part 71, a rear half
portion of the bulge containing part 71 is further bulged to form a
clutch containing part 71c for containing the twin clutch 41, and a
front half portion of the bulged containing part 71 forms a gear
containing part 71g for containing a pair of the primary drive gear
44 and the primary driven gear 43 which are meshed with each other
and transmit power from the crankshaft 30 to the twin clutch
41.
The right case cover 70 projects from a side wall into a space on
the lower side of the bulge containing part 71 to form a clutch
actuator containing part 72 for containing therein an upper-lower
pair of a first clutch actuator 81A and a second clutch actuator
81B.
The clutch actuator containing part 72 has a rectangular tubular
shape oriented in the front-rear direction, in which a valve case
72v is formed in a front half, and a solenoid case 72s is formed in
a rear half.
The valve case 72v has a structure in which respective valve
element driving parts 81Av and 81Bv of the first and second clutch
actuators 81A and 81B are respectively inserted into circular holes
which are bored on upper and lower sides while oriented in the
front-rear direction and are closed at their front ends. The
solenoid case 72s is provided at its rear end with a clutch
actuator mounting/dismounting port 72h oriented rearward, opened in
a vertically long rectangular shape and exposed to the exterior
(see FIG. 9); respective linear solenoids 81As and 81Bs of the
first and second clutch actuators 81A and 81B are inserted, while
aligned on the upper and lower sides, in an internal common
space.
Referring to FIGS. 5 and 6, the first and second clutch actuators
81A and 81B are inserted as one body via the clutch actuator
mounting/dismounting port 72h into the clutch actuator containing
part 72, in the condition where those base parts of the valve
element drive parts 81Av and 81Bv which are connected to the
solenoids 81As and 81Bs are supported by a support plate 82. In the
inside of the clutch actuator containing part 72, the support plate
82 is anchored by a bolt 82b (see FIG. 4). The clutch actuator
mounting/dismounting port 72h is closed with a rectangular
plate-shaped clutch actuator cover member 83 (see FIGS. 12 and 13),
and four corners of the clutch actuator cover member 83 are screwed
by bolts 83b.
In addition, the right case cover 70 has a structure in which an
oil filter housing 73 of an oil filter 85 is formed to project from
a side wall, on the front side of the clutch actuator containing
part 72 in the space on the lower side of the bulge containing part
71. Therefore, the oil filter 85 can be provided without enlarging
the internal combustion engine E in overall left-right width or
overall front-rear width, and it is possible to avoid an
enlargement of the size of the internal combustion engine E.
The oil filter housing 73 is not formed separately from the right
case cover 70 but formed integrally with the right case cover 70,
which leads to a reduction in the number of component parts and to
favorable maintainability.
The oil filter housing 73 has a cylindrical shape with a center
axis oriented in the front-rear direction, its rear end proximate
to the valve case 72v of the clutch actuator containing part 72 is
closed, it is formed at its front end with a filter element
mounting/dismounting port 73h being opened toward the front side in
a circular shape and exposed to the exterior (see FIG. 10), and a
filter element 86 is inserted therein from the front side (see FIG.
5).
The oil filter housing 73 cylindrical in shape is formed at such a
position as to overlap with the clutch actuator containing part 72
in front view shown in FIG. 10, and is restrained from projecting
sideways. In addition, since the oil filter housing 73 is
cylindrical in shape and therefore its corners do not project
sideways, the bank angle of the vehicle body can be designed to be
large.
Incidentally, as shown in FIG. 6, the oil filter housing 73 is
projected toward the right side relative to the clutch actuator
containing part 72, and the clutch actuator containing part 72 is
formed on the inner side relative to an outside portion of the oil
filter housing 73 in the vehicle body width direction (see FIGS. 9
and 10). Therefore, the oil filter housing 73 serves as a shield,
by which the clutch actuators 81A and 81B can be protected against
flying stones and the like coming from the front side.
The filter element mounting/dismounting port 73h oriented forward
is closed with a circular plate-shaped filter cover member 87 (see
FIGS. 14 and 15) put from the front side. The filter cover member
87 is anchored by two bolts 87b screwed at upper and lower
positions.
As shown in FIG. 17, the oil filter housing 73 is located at such a
position as to cover a lower portion of the control oil pump case
51 from the right side. A circular hole communicating with the
inside of the oil filter housing 73 is formed to face the discharge
port 51h of the control oil pump case 51, both of them are
interconnected by a connection pipe 74 (see FIG. 4), and the oil
discharged from the control oil pump 50 is led through the
discharge oil passage 56 and the connection pipe 74 to the upstream
side of the filter in the oil filter housing 73.
A connection oil pipe 75 is formed between the center of a rear
wall of the oil filter housing 73 and the valve case 72v
constituting a front half of the clutch actuator containing part
72. The connection oil pipe 75 communicates with the downstream
side of the filter in the center of the filter element 86.
Therefore, the oil filtered by the filter element 86 of the oil
filter 85 is supplied through the connection oil pipe 75 into the
valve case 72v.
Incidentally, referring to FIGS. 14 and 15, the filter cover member
87 is provided with a mount boss part 87s for mounting a discharge
oil pressure sensor 88, the mount boss part 87s being projectingly
formed at an eccentric position. The mount boss part 87s is
provided with a circular hole 87h in which to insert a pressure
sensing part of the discharge oil pressure sensor 88, the circular
hole 87h being bored from the face side to the back side. The tip
of the circular hole 87h is tapered, and is then opened to the back
side via a small hole.
Therefore, the oil discharged from the control oil pump 50 is led
through the connection pipe 74 to the upstream side of the filter
in the oil filter housing 73. Further, the discharged oil enters
into the circular hole 87h in the filter cover member 87, to reach
the pressure sensing part of the discharge oil pressure sensor 88,
so that the discharge oil pressure sensor 88 detects the pressure
of the oil discharged from the control oil pump 50.
The oil supplied from the oil filter 85 into the valve case 72v of
the clutch actuator containing part 72 is distributed to the
respective valve element driving parts 81Av and 81Bv of the first
and second clutch actuators 81A and 81B. Then, the working oils
controlled by the valve element driving parts 81Av and 81Bv driven
by the linear solenoids 81As and 81Bs respectively are served to
drive control of the first and second friction clutches 41A and 41B
of the twin clutch 41.
Therefore, the right case cover 70 is provided with a pair of
mutually parallel, first and second control oil passages 76A and
76B which offer rectilinear connection between the valve case 72v
of the clutch actuator containing part 72 and a central portion of
the clutch containing part 71c containing the twin clutch 41
therein; the first and second control oil passages 76A and 76B are
formed to expand in tubular shape on the surface of the right case
cover 70.
The valve case 72v of the clutch actuator containing part 72 is
located on a front lower side of the clutch containing part 71c
located at an upper portion of the rear half of the right case
cover 70. Accordingly, the first and second control oil passages
76A and 76B extend rearwardly upward from the valve case 72v.
The center of the clutch containing part 71c supports a portion
near the right end of the crankshaft 35 through a bearing 77,
together with the clutch inner of the first friction clutch 41A. In
addition, a bottomed cylinder part 71cc covering the right end of
the crankshaft 35 is formed to bulge to the right side. The first
and second control oil passages 76A and 76B are connected to the
bottomed cylinder part 71cc, and communicate with the inside of the
latter.
A partition member 78 is interposed between an inner peripheral
surface of the bottomed cylinder part 71cc and an outer peripheral
surface of the right end of the crankshaft 35.
The partition member 78 is provided, at both ends of its
cylindrical portion fitted to the right end of the crankshaft 35,
with flange parts having an outside diameter equal to the inside
diameter of the bottomed cylinder part 71cc. The inside of an outer
peripheral groove between both the flange parts is divided into two
spaces.
The outer peripheral groove on one side, which communicates with
the first control oil passage 76A as the upper-side one of the pair
of first and second control oil passages 76A and 76B oriented
slantly, penetrates the cylindrical portion of the partition member
78 and the right end of the crankshaft 35, to communicate with the
in-shaft oil passage 49a. The outer peripheral groove on the other
side, which communicates with the second control oil passage 76B on
the lower side, penetrates the outer-side (right-side) flange part
of the partition member 78, and extends around along a bottom
surface of the bottomed cylinder part 71cc, to communicate with the
in-shaft oil passage 49b.
Therefore, the working oil controlled by driving of the first
clutch actuator 81A is supplied through the first control oil
passage 76A and the in-shaft oil passage 49a to the first friction
clutch 41A, to effect engagement/disengagement of the first
friction clutch 41A. The working oil controlled by driving of the
second clutch actuator 81B is supplied through the second control
oil passage 76B and the in-shaft oil passage 49B, to effect
engagement/disengagement of the second friction clutch 41B.
With the first and second clutch actuators 81A and 81B controlled
in a coordinated manner, drivings of the first and second friction
clutches 41A and 41B are mutually controlled in timing, whereby
shifting of the transmission T is carried out smoothly.
As above-mentioned, an upper half portion of the right case cover
70 is bulged to the right side to form the bulge containing part
71, and the clutch actuator containing part 72 is projectingly
formed on the front lower side of the clutch containing part 71c
further bulged from a rear half portion of the bulge containing
part 71. Therefore, on the lower side of the clutch containing part
71c and on the rear side of the clutch actuator containing part 72,
a recessed space S is formed which is opened on the three sides,
namely, the rear side, the lower side and the right side.
The first and second control oil passages 76A and 76B are formed in
the state of being oriented slantly while interconnecting the
bottomed cylinder part 71cc at the center of the clutch containing
part 71c with the valve case 72v as the front portion of the clutch
actuator containing part 72, and, therefore, they do not interfere
with the recessed space S. Accordingly, the recessed space S is
largely opened on the right side.
Incidentally, the slantly oriented first control oil passage 76A on
the upper side, of the right case cover 70, is provided at a
substantially central position thereof with a sensor mounting boss
part 76Ab having a mounting port directed upward. The second
control oil passage 76B on the lower side is provided with a sensor
mounting boss part 76Bb having a mounting port directed rearward,
between the clutch containing part 71c and the clutch actuator
containing part 72.
A first control oil pressure sensor 79A is mounted to the sensor
mounting boss part 76Ab of the first control oil passage 76A on the
upper side, in the state of being oriented in the vertical
direction and projecting upward; on the other hand, a second
control oil pressure sensor 79B is mounted to the sensor mounting
boss part 76Bb of the second control oil passage 76B on the lower
side, in the state of being oriented in the front-rear direction
and projecting rearward (see FIG. 5).
The first control oil pressure sensor 79A detects the oil pressure
in the first control oil passage 76A for effecting
engagement/disengagement of the first friction clutch 41A, and the
second control oil pressure sensor 79B detects the oil pressure in
the second control oil passage 76B for effecting
engagement/disengagement of the second friction clutch 41B. The oil
pressures thus detected are served for enhancing the shift control
properties of the twin clutch 41.
As shown in FIG. 2, the first control oil pressure sensor 79A
mounted to the first control oil passage 76A in the state of being
oriented in the vertical direction and the second control oil
pressure sensor 79B mounted to the second control oil passage 76B
in the state of being oriented in the front-rear direction are both
located at a peripheral edge portion of the bulged clutch
containing part 71c of the right case cover 70, and can be provided
in a compact form at such positions that they do not interfere with
the twin clutch 41 and that their projection to a lateral side is
minimized.
In this embodiment, as shown in FIG. 10, the first control oil
pressure sensor 79A (indicated by two-dotted chain line in FIG. 10)
is disposed compactly on the inner side (the left side of the
vehicle body) relative to the bottomed cylinder part 71cc bulged at
the center of the clutch containing part 71c of the right case
cover 70.
Similarly, as shown in FIG. 9, the second control oil pressure
sensor 79B (indicated by two-dotted chain line in FIG. 9) is
disposed compactly on the inner side relative to the bottomed
cylinder part 71cc at the center of the clutch containing part
71c.
The right case cover 70 in this internal combustion engine E is
integrally provided with the clutch actuator containing part 72 in
which to contain the first and second clutch actuators 81A and 81B
for effecting engagement/disengagement of the twin clutch 41, the
clutch actuator containing part 72 being projected sideways. In
addition, the clutch actuator mounting/dismounting port 72h of the
clutch actuator containing part 72 is formed to be exposed to the
exterior. Therefore, the first and second clutch actuators 81A and
81B contained in the clutch actuator containing part 72 can be put
in and out through the clutch actuator mounting/dismounting port
72h, without need to dismount the right case cover 70.
Consequently, maintainability is extremely good.
Besides, in this structure, the clutch actuator containing part 72
formed to project to a lateral side of the right case cover 70 has
the clutch actuator mounting/dismounting port 72h formed to be
exposed to the exterior; therefore, the clutch actuator mounting
structure is simplified.
The right case cover 70 is provided with the bulge containing part
71 which has an upper half portion composed generally of the clutch
containing part 71c and a gear containing part 71g and which is
bulged sideways. Besides, the clutch actuator containing part 72 is
projectingly formed by utilizing the space on the lower side of the
bulge containing part 71. Therefore, as shown in FIG. 9, the clutch
actuator containing part 72 is restrained from projecting sideways,
and is compactly disposed on the inner side (the left side of the
vehicle body) relative to the bottomed cylinder part 71cc bulged at
the center of the clutch containing part 71c of the right case
cover 70. In addition, as shown in FIGS. 2 and 5, notwithstanding
the longitudinal direction of the clutch actuator containing part
72 being oriented in the front-rear direction, the clutch actuator
containing part 72 is contained within the front-rear width of the
bulged containing part 71 on the upper side.
Accordingly, the clutch actuator containing part 72 can be formed
without enlarging the internal combustion engine E in overall
left-right width or overall front-rear width, so that it is
possible to avoid an enlargement of the size of the internal
combustion engine E.
In addition, the oil filter housing 73 is formed on the front side
of the clutch actuator containing part 72, in such a shape that the
cylinder center axis of the cylindrical filter element 86 is
oriented in the front-rear direction and that the filter element
mounting/dismounting port 73h is directed forward. The clutch
actuator containing part 72 is formed with the clutch actuator
mounting/dismounting port 72h directed rearward. Therefore,
notwithstanding the clutch actuator containing part 72 and the oil
filter housing 73 being disposed proximate to each other, the first
and second clutch actuators 81A and 81B and the filter element 86
can be mounted and dismounted without interference with each other
(see FIG. 5). Therefore, while good maintainability is secured, the
first and second clutch actuators 81A and 81B and the oil filter 85
juxtaposed in the front-rear direction can be kept small in the
front-rear width, and an enlargement of the size of the internal
combustion engine E can be avoided.
As shown in FIG. 2, the clutch actuator containing part 72 is
formed at such a vertical position that its lower end is proximate
to or in contact with the lower end edge of the right case cover
70. Therefore, the clutch actuator containing part 72 can be
disposed as low as possible, whereby lowering of the center of
gravity can be contrived. In addition, the oil filter 85 is so
formed that its upper end is located at substantially the same
vertical position as the upper end of the clutch actuator
containing part 72. This ensures that the space on the upper side
of the clutch actuator containing part 72 and the oil filter 85
having their upper ends at substantially the same vertical position
is effectively utilized for the twin clutch 41, the pair of the
primary drive gear 44 and the primary driven gear 43, and the
like.
The first and second clutch actuators 81A and 81B are provided on
the front lower side of the twin clutch 41. The pair of first and
second control oil passages 76A and 76B for supplying the working
oil from the first and second clutch actuators 81A and 81B to the
respectively corresponding first and second friction clutches 41A
and 41B are formed at the outside surface of the right case cover
70 in the state of being oriented obliquely and extending
rectilinearly in parallel to each other. Accordingly, the right
case cover 70 is provided with the recessed space S on the rear
side of the first and second clutch actuators 81A and 81B and on
the lower side of the twin clutch 41, where the first and second
control oil passages 76A and 76B do not interfere. The recessed
space S is opened on the rear side, the lower side and the outer
side, to form a space suitable for mounting the driver's foot.
As shown in FIGS. 1 and 2, when the driver seated on the
tandem-type seat 17 put his or her foot Pf on the foot step 21, the
tip of the foot Pf is contained within the recessed space S.
Incidentally, the second control oil pressure sensor 79B mounted to
the second control oil passage 76B is disposed at a lower portion
of the peripheral edge of the clutch containing part 71c in the
state of being oriented in the front-rear direction. Therefore, the
second control oil pressure sensor 79B does not interfere with the
recessed space S and, therefore, does not obstruct the disposition
of the tip of the foot Pf within the recessed space S.
Accordingly, the foot Pf of the driver P can be set in an optimum
position, without needlessly protruding to the right outer
side.
The oil discharged from the control oil pump 50 is led into the oil
filter housing 73 of the oil filter 85. The discharge oil pressure
sensor 88 for detecting the pressure of the discharged oil is
forwardly projectingly provided while being mounted to the housing
cover member 87 for closing the filter element mounting/dismounting
port 73h directed forward of the oil filter housing 73. Therefore,
the discharge oil pressure sensor 88 can be provided utilizing the
space on the front side of the oil filter 85, and its projection
from the internal combustion engine E is avoided as securely as
possible. In addition, with the discharge oil pressure sensor 88
preliminarily mounted to the housing cover member 87 so that they
can be handled as one body, workability can be enhanced.
Although a specific form of embodiment of the instant invention has
been described above and illustrated in the accompanying drawings
in order to be more clearly understood, the above description is
made by way of example and not as a limitation to the scope of the
instant invention. It is contemplated that various modifications
apparent to one of ordinary skill in the art could be made without
departing from the scope of the invention which is to be determined
by the following claims.
* * * * *